In a breakthrough researchers have discovered a way of reducing the fertility of malaria-carrying mosquitoes potentially providing a new tactic to combat the disease. The catch lies in the sperm that the female mosquitoes store in their bodies and repeatedly take sperm over the course of their lifetime to fertilise the eggs that they lay. There sperm are partly protected by the actions of an enzyme called HPX15. When the researchers interfered with HPX15 in female Anopheles gambiae mosquitoes in the laboratory the females fertilised fewer eggs and therefore produced fewer offspring. 'The research suggests a way that we might